1. Field of the Invention
This invention is directed to a data recording system for a databack of a camera. Specifically, this invention is directed to an information recording system which records copyright, name, time and date data on a photographic recording medium. This system is also directed to a system for ensuring the correct date and/or time information is recorded. More specifically, the system is useful for a databack of a camera.
2. Description of Related Art
Heretofore, a databack (data recording system) which is an accessory system of a camera and which records data including date information and copyright information was described in Japanese Patent Application 1991-318631. This data recording system uses an array of light emitting diodes (LEDs) to optically record and/or display date information, time information and/or information including the photographer's name inside or outside of the photographic screen on the film. The date and/or time of the photograph are automatically recorded by this system, making it beneficial when arranging photographs later and with commemorative photographs. This data recording system is also valuable in asserting copyrights because it can automatically record the necessary copyright information on the surface of the film. The data to be recorded is displayed by a liquid crystal display element (LCD) so that the information can be verified by the photographer before it is recorded.
With this kind of data recording system, it is necessary to have an electrical circuit, or timer, which maintains one or more of time data, date data or name data. In general, a microprocessor is used as this electrical circuit, with a liquid crystal oscillator connected to the microprocessor to provide clock signals to the microprocessor. The microprocessor is able to record the correct time by adding these precise clock signals from the liquid crystal oscillator to stored time and date data. In addition, to record the copyright information, a selective memory means which allows the photographer's name to be recorded is also provided using the same microprocessor.
On the other hand, it is necessary to have a reset circuit connected to the microprocessor. This reset circuit resets the microprocessor when a new battery is connected to the databack and current is first supplied after the battery is changed.
When the microprocessor is reset, the time data is measured from an initial value, which is preset in the device. Because the initial value of this time data is set as a time prior to when photographs are actually be taken (a previous date and time), it is necessary for the user to adjust the time data to the correct date and time in a well-known manner whenever the battery is replaced.
With conventional databacks (data recording systems), it is possible for data to be displayed on the film even after the time data is reset as described above. Because of this, the incorrect time data calculated by measuring time from the initial value (a previous date and time) is recorded if the user forgets to make the necessary adjustments.
Furthermore, this resetting problem is not limited to when the battery is replaced, but rather the problem described above can occur spontaneously because the reset circuit also functions at times other than when the battery is replaced, such as when the connection with the battery is broken for an instant due to vibration or when static electric noise enters from the outside. Thus, the user is often not aware that the timer has been reset.
In this kind of circumstance, the wrong time data is displayed if the user does not notice that the time displayed on the external LCD has been reset to a previous value, making both the time/date stop on the photograph wrong and the assertion of copyrights impossible, thereby defeating the main purposes of the device.